Shunt Outcome Research Articles

Primary Patency Success of Arteriovenous Shunts in Hemodialysis Patients: A 28-Month Prospective Study.

Background Arteriovenous (AV) shunts are vital for providing long-term vascular access in hemodialysis patients. While brachiocephalic and radiocephalic shunts are commonly employed, data on their primary patency rates and associated complications in resource-limited settings such as Yemen remain scarce. This study aimed to evaluate the primary patency success of AV shunts and identify factors influencing their outcomes in hemodialysis patients at Al-Thawra Modern General Hospital. Methods This prospective observational study was conducted over 28 months, from April 2021 to August 2023, at Al-Thawra Modern General Hospital in Sana'a, Yemen. A total of 163 patients with chronic renal failure requiring AV shunt creation for hemodialysis were included. Data on patient demographics, comorbidities, shunt characteristics, and postoperative outcomes were collected. Primary patency was assessed at the 8-month follow-up interval. Statistical analysis was performed to identify factors associated with shunt patency. Results Among the enrolled 163 patients, the median age was 43.12 years, with 61.3% undergoing brachiocephalic shunt creation. The overall primary patency rate at 8 months was 87.7%, with brachiocephalic shunts exhibiting a significantly greater patency rate (93.0%) than radiocephalic shunts (67.3%) (p = 0.02). Complications occurred in 25% of patients, with pseudoaneurysm formation being the most common complication (6.1%). Factors such as shunt type, patient age, and comorbidities (e.g., diabetes) significantly influence patencyoutcomes. Conclusion Compared with radiocephalic shunts, brachiocephalic shunts demonstrated superior primary patency rates, suggesting that they may be a preferable option for long-term hemodialysis access in the studied population. These findings emphasize the need for individualized patient management and careful postoperative monitoring, particularly in resource-limited settings such as Yemen, to optimize AV shunt outcomes.

Blood-brain barrier-associated biomarker correlated with cerebral small vessel disease and shunt outcome in normal pressure hydrocephalus: a prospective cohort study.

Blood-brain barrier (BBB) breakdown is associated with neurodegeneration and cognitive impairment. Cerebral small vessel disease (CSVD) is also common in idiopathic normal pressure hydrocephalus (iNPH). Biomarkers in the cerebrospinal fluid (CSF) may reflect the severity of neuropathological damage and indicate a relationship between BBB integrity and iNPH and its surgical outcome. We investigated the association of CSVD and comorbidity-related CSF biomarkers with shunt outcomes in iNPH. This prospective cohort study recruited 53 patients with iNPH, who were subgrouped by CSVD severity. CSF proteins were analyzed, including soluble platelet-derived growth factor receptor-β (sPDGFR-β), Alzheimer's disease biomarkers, neurofilament light chain (NfL), and triggering receptor expressed on myeloid cells 2 (Trem2). We assessed symptom improvement, investigated its association with biomarkes levels, calculated protein cutoffs for surgical outcomes using receiver operating characteristic (ROC) curves, and compared model predictions using different proteins using hierarchical regression analysis. Among patients with iNPH, 74% had comorbid CSVD. Patients with severe CSVD exhibited significantly higher sPDGFR-β levels (P=0.019) and better postoperative performance (β=0.332, t=2.174, P=0.039; r=0.573, P=0.001). Analysis of the predictive potential of the biomarkers showed that sPDGFR-β was predictive of surgical outcomes (area under curve=0.82, sensitivity=66.8%, specificity=94.7%). A Comparison of the models revealed a greater effect of sPDGFR-β (Adjusted R2=0.247, ∆R2=0.160, ∆F(1, 37)=8.238, P=0.007) on cognitive improvement. This study highlighted the relevance of CSF biomarkers in assessing CSVD severity and predicting iNPH surgical outcome. CSF shunt surgery may provide an alternative treatment for neurodegenerative diseases with BBB breakdown and dysfunctional CSF clearance.

Influence of distal insertion technique, valve selection, and patient demographics on shunt survival in ventriculoperitoneal shunt insertion: A retrospective analysis of an Australian case series

BackgroundVentriculoperitoneal (VP) shunt insertion is a means of diverting cerebrospinal fluid (CSF) for management of hydrocephalus. Revision rates, operating time, and length of stay (LOS) following laparoscopic insertion of the distal catheter have been mixed. There are limited data on the role of adhesiolysis during VP shunt insertion. Valve characteristics have also been shown to influence patient outcomes. There is a paucity of Australian data reporting on the effect of these variables on shunt outcomes. We aimed to study patient demographics, indications, and surgical and instrument variables in the Australian context. MethodsWe performed a retrospective, multi-surgeon, single-centre analysis of VP shunts inserted in adults via an open or laparoscopic technique. Data on patient demographics and surgery characteristics were collected from the hospital medical records and the Australasian Shunt Registry. The primary outcome was shunt revision rate and secondary outcomes were postoperative complications, operating time and LOS, and shunt survivability. ResultsFifty-six participants were eligible for analysis. The overall revision rate was 14.3 %, which was lower than the national average. The distal catheter revision rate was 0 %. Laparoscopic insertion of the distal catheter was shown to significantly reduce operating time (70.4 min in the open group and 50.7 min in the laparoscopic group, p < 0.001). This was demonstrated across different aetiologies, and when controlling for age and valve-type (p < 0.05). The revision rate of non-programmable was higher than programmable valves (42.9 % versus 2.9 %, respectively). There were no differences between previous abdominal surgery, LOS, complication, or revision rate between open and laparoscopic insertion. VP shunt survivability was greater in the laparoscopic group (90-day shunt survival of 96.7 % and 92 % in the laparoscopy and open groups, respectively; p > 0.05). We did not find any significant difference in operating time or length of stay for age, sex, or previous abdominal surgery, even when accounting for surgical technique. Indication and shunt survivability varied widely between age groups. The use of laparoscopic insertion increased over time, though surgeons did not crossover techniques. ConclusionsThe overall distal revision rate of VP shunts is low. Laparoscopic insertion of the distal catheter reduces operating time and may improve shunt survivability. Larger studies are needed to confirm differences in shunt survivability in open versus laparoscopic distal catheter insertion, between age groups, clinical indications, and valve type on patient outcomes.

Ventriculoperitoneal shunting obstruction: a multicentre clinical audit for cerebrospinal fluid parameters and its prediction role.

Shunt obstruction is a type of ventriculoperitoneal shunt (VPS) failure. Whether changes in cerebrospinal fluid (CSF) parameters can influence shunt outcomes or not is debatable. In this study, we retrospectively included adult hydrocephalus patients who received VPS from 6 general hospitals in different provinces of China from November 2013 to September 2021. The inclusion criteria: Patients with hydrocephalus of all etiologies underwent shunt surgery from 6 general hospitals in different provinces of China were included in the study. The exclusion criteria: 1.Patients under the age of 18; 2.Patients who had previous shunt surgery; 3. Shunt failurefromother factors; 4.Patients died from other causes; 5. Patients with incomplete data. The CSF of shunt patients had been analyzed at the time of shunt insertion. The CSF samples were collected and analyzed when the shunt was implanted. The relationship between CSF parameters and the incidence rate of shunt obstruction in one year was analyzed. A total of 717 eligible patients from 6 hospitals were included, of whom 59(8.23%) experienced obstruction. Multivariate logistic regression analysis identified that protein level(odds ratio [OR] 1.161, 95% CI 1.005 ~ 1.341, p = 0.043), decreased glucose level(< 2.5 mmol/L)(odds ratio 3.784, 95% confidence interval 1.872 ~ 7.652, p = 0.001) and protein level increase(> 0.45 g/L) (odds ratio 3.653, 95% confidence interval 1.931 ~ 6.910, p = 0.001)were independent risk factors of shunt obstruction. This study suggested that increased protein level (> 0.45 g/L) and decreased glucose level (< 2.5 mmol/L) in CSF indicated an increased risk of shunt obstruction in a patient with hydrocephalus. Thus, shunt surgery should be more carefully considered when the CSF glucose and protein were abnormal.

923 Utilization of a Gestational Age Threshold May Improve Pediatric VP Shunt Outcomes

INTRODUCTION: The highest shunt failure rates occur in patients with hydrocephalus from intraventricular hemorrhage of prematurity (Premie-IVH). Tuli et al (1999) described a 40-week gestational age threshold that significantly differentiated shunt failure rates in a neonatal hydrocephalus population, but this threshold has not been investigated in a dedicated Premie-IVH cohort. METHODS: A retrospective cohort study was performed on patients treated for hydrocephalus with VP shunt implant at an academic pediatric institution from 2010-2021. Inclusion criteria were hydrocephalus from Premie-IVH, known gestational age at delivery, 1 year of follow-up, and known surgical history prior to VP shunt implant. RESULTS: Among 32 Premie-IVH patients, 50% experienced shunt failure within 1 year after VP shunt implant. Average gestational age (GA) at delivery was 27.5 weeks and average GA at surgery was 45.2 weeks. In total, 44% of patients received a VP shunt before 40 weeks of gestational age. In this population, 64% experienced VP shunt failure within one year and had an average of 0.79 temporizing surgeries prior to VP shunt implant. In the 56% of patients who received VP shunt surgery after 40 weeks of GA, 39% experienced VP shunt failure within one year and had an average of 1.3 temporizing surgeries prior to VP shunt surgery. CONCLUSIONS: In patients with hydrocephalus from Premie-IVH, those who had VP shunt surgery after 40 weeks gestational age received a greater number of temporizing measures while experiencing a 49% lower VP shunt failure rate. Temporizing measures may be used to improve VP shunt outcomes by delaying VP shunt surgery until after 40 weeks gestational age.

Optimization of number and range of shunt valve performance levels in infant hydrocephalus: a machine learning analysis.

Shunt surgery is the main treatment modality for hydrocephalus, the leading cause of brain surgery in children. The efficacy of shunt surgery, particularly in infant hydrocephalus, continues to present serious challenges in achieving improved outcomes. The crucial role of correct adjustments of valve performance levels in shunt outcomes has been underscored. However, there are discrepancies in the performance levels of valves from different companies. This study aims to address this concern by optimizing both the number and range of valve performance levels for infant hydrocephalus, aiming for improved shunt surgery outcomes. We conducted a single-center cohort study encompassing infant hydrocephalus cases that underwent initial shunt surgery without subsequent failure or unimproved outcomes. An unsupervised hierarchical machine learning method was utilized for clustering and reporting the valve drainage pressure values for all patients within each identified cluster. The optimal number of clusters corresponds to the number of valve performance levels, with the valve drainage pressure ranges within each cluster indicating the pressure range for each performance level. Comparisons based on the Silhouette coefficient between 3-7 clusters revealed that this coefficient for the 4-cluster (4-performance level) was at least 28.3% higher than that of other cluster formations in terms of intra-cluster similarity. The Davies-Bouldin index for the 4-performance level was at least 37.2% lower than that of other configurations in terms of inter-cluster dissimilarity. Cluster stability, indicated by a Jaccard index of 71% for the 4-performance level valve, validated the robustness, reliability, and repeatability of our findings. Our suggested optimized drainage pressure ranges for each performance level (1.5-5.0, 5.0-9.0, 9.0-15.0, and 15.0-18.0cm H2O) may potentially assist neurosurgeons in improving clinical outcomes for patients with shunted infantile hydrocephalus.

Shunt timing in low-weight infants in the treatment of hydrocephalus.

The optimal timing of ventricular shunt placement in low-weight and preterm infants remains an unresolved topic in modern pediatric neurosurgery. Shunt placement for hydrocephalus is performed over a wide range of infant weights, and the standard weight threshold for shunt placement can vary substantially across institutions. The aim of this study was to investigate shunt outcome in infants of low body weight. An IRB-approved retrospective analysis of 76 infants (29 females, 47 males) who received primary shunt placement between 2003 and 2018 was performed. Uniform criteria were used over the entire dataset to determine the safety for ventriculoperitoneal (VP) shunt placement: 1) weight near or above 1500 g, 2) feeding tolerance, and 3) lack of necrotizing enterocolitis or active systemic infection. Infants were classified into a low-weight (LW) (< 2000 g) or standard weight (SW) (2000-3000 g) group based on their body weight at the time of initial shunt placement. Shunt survival was compared between the groups. The threshold weight separating the LW and SW groups and outcomes was additionally varied and systematically reanalyzed. Shunts were placed in 24 LW infants and 52 SW infants over the inclusion period. Etiologies for hydrocephalus were similar across groups: predominantly intraventricular hemorrhage (54%) (p = 0.13) and open neural tube defect (29%) (p = 0.61). Both LW and SW groups had 58% 1-year shunt survival rates. Overall, 46% of shunts failed in the LW group compared with 54% in the SW group over a median follow-up of 47 months (range 0-170 months). A log-rank test comparing shunt survival rates did not show significance (p = 0.43). Groups were repartitioned using a range of threshold weights (1600-2400 g) to divide LW from SW infants. The lack of association between VP shunt placement in LW infants and time frame of revision was consistently observed over the full range of varied threshold weights. There was no significant difference in overall time to shunt revision between infants weighing < 2000 g and infants weighing 2000-3000 g. No correlation between weight and shunt survival was detected. Combined with other clinical features pertinent to the management of hydrocephalus in the neonatal population, this investigation provides insight toward clinical decision-making regarding infants of low birth weight and suggests that further multi-institutional study on this topic is warranted.

Neuronal pentraxin 2 correlates with neurodegeneration but not cognition in idiopathic normal pressure hydrocephalus (iNPH).

Neuronal pentraxin-2 (NPTX2) is a synaptic protein responsible for modulating plasticity at excitatory synapses. While the role of NPTX2 as a novel synaptic biomarker in cognitive disorders has been elucidated recently, its role in idiopathic normal pressure hydrocephalus (iNPH) is not yet understood. To determine if NPTX2 predicts cognition in patients with iNPH, and whether it could serve as a predictive marker for shunt outcomes. 354 iNPH patients underwent cerebrospinal fluid drainage (CSF) as part of the tap test or extended lumbar drainage. Demographic and clinical measures including age, Evans Index (EI), Montreal Cognitive Assessment (MoCA) score, Functional Activities Questionnaire (FAQ) score, and baseline and post-shunt surgery Timed Up and Go (TUG) test scores were ascertained. CSF NPTX2 concentrations were measured using an ELISA. CSF β-amyloid 1-40 (Aβ1-40), β-amyloid 1-42 (Aβ1-42), and phosphorylated tau-181 (pTau-181) were measured by chemiluminescent assays. Spearman's correlation was used to determine the correlation between CSF NPTX2 concentrations and age, EI, MoCA and FAQ, TUG, Aβ1-40/Aβ1-42 ratio, and pTau-181 concentrations. Logistic regression was used to determine if CSF NPTX2 values were a predictor of short-term improvement post-CSF drainage or long-term improvement post-shunt surgery. There were 225 males and 129 females with a mean age of 77.7 years (± 7.06). Average CSF NPTX2 level in all iNPH patients was 559.97 pg/mL (± 432.87). CSF NPTX2 level in those selected for shunt surgery was 505.61 pg/mL (± 322.38). NPTX2 showed modest correlations with pTau-181 (r = 0.44, p < 0.001) with a trend for Aβ42/Aβ40 ratio (r = -0.1, p = 0.053). NPTX2 concentrations did not correlate with age (r = -0.012, p = 0.83) or MoCA score (r = 0.001, p = 0.87), but correlated negatively with FAQ (r = -0.15, p = 0.019). While CSF NPTX2 values correlate with neurodegeneration, they do not correlate with cognitive or functional measures in iNPH. CSF NPTX2 cannot serve as a predictor of either short-term or long-term improvement after CSF drainage. These results suggest that synaptic degeneration is not a core feature of iNPH pathophysiology.

Prediction of Surgical Outcomes in Normal Pressure Hydrocephalus by MR Elastography.

Normal pressure hydrocephalus is a treatable cause of dementia associated with distinct mechanical property signatures in the brain as measured by MR elastography. In this study, we tested the hypothesis that specific anatomic features of normal pressure hydrocephalus are associated with unique mechanical property alterations. Then, we tested the hypothesis that summary measures of these mechanical signatures can be used to predict clinical outcomes. MR elastography and structural imaging were performed in 128 patients with suspected normal pressure hydrocephalus and 44 control participants. Patients were categorized into 4 subgroups based on their anatomic features. Surgery outcome was acquired for 68 patients. Voxelwise modeling was performed to detect regions with significantly different mechanical properties between each group. Mechanical signatures were summarized using pattern analysis and were used as features to train classification models and predict shunt outcomes for 2 sets of feature spaces: a limited 2D feature space that included the most common features found in normal pressure hydrocephalus and an expanded 20-dimensional (20D) feature space that included features from all 4 morphologic subgroups. Both the 2D and 20D classifiers performed significantly better than chance for predicting clinical outcomes with estimated areas under the receiver operating characteristic curve of 0.66 and 0.77, respectively (P < .05, permutation test). The 20D classifier significantly improved the diagnostic OR and positive predictive value compared with the 2D classifier (P < .05, permutation test). MR elastography provides further insight into mechanical alterations in the normal pressure hydrocephalus brain and is a promising, noninvasive method for predicting surgical outcomes in patients with normal pressure hydrocephalus.

Choosing wisely: adjustable or fixed pressure valves for patients with idiopathic normal hydrocephalus? A systematic review and meta-analysis on ventriculoperitoneal shunt outcomes

Choosing wisely: adjustable or fixed pressure valves for patients with idiopathic normal hydrocephalus? A systematic review and meta-analysis on ventriculoperitoneal shunt outcomes

Outcomes of Portosystemic Shunts in Children with and without Liver Transplantation.

Limited data exist regarding outcome and morbidity associated with portosystemic shunts in the pediatric transplant population. Our study assesses the outcomes of pediatric patients who underwent a portosystemic shunt procedure, both with and without liver transplantation (LT). This study retrospectively reviewed the medical records of pediatric patients aged 0-19 years who underwent shunt placement between 2003 and 2017 at a tertiary care center. The analysis included cases of shunt placement with or without LT. A total of 13 pediatric patients were included in the study with median age of 8.8 years. Among the cases, 11 out of 13 (84.6%) underwent splenorenal shunt, 1 (7.7%) underwent a mesocaval shunt, and another 1 (7.7%) underwent a Modified Rex (mesoportal) shunt. Additionally, 5 out of 13 (38.5%) patients had LT, with 4 out of 5 (80.0%) receiving the transplant before shunt placement, and 1 out of 5 (20.0%) receiving it after shunt placement. Gastrointestinal bleeding resulting from portal hypertension was the indication in all cases. A total of 10 complications were reported in 5 patients; the most common complication was anemia in 3 (23.1%) patients. At the most recent follow-up visit, the shunts were functional without encephalopathy, and no deaths were reported. Shunt placement plays a crucial role in the management of patients with portal hypertension. Our study demonstrates favorable long-term outcomes in pediatric patients who underwent shunt placement. Long term shunt outcomes were similar and unremarkable in patients with LT and without LT.

Compare the safety and efficacy of endoscopic third ventriculostomy and ventriculoperitoneal shunt placement in infants and children with hydrocephalus: a systematic review and meta-analysis

Purpose Endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt placement are two surgical options used for treatment of non-communicating hydrocephalus. The purpose of this study was to compare the efficiency and safety of these techniques in pediatric patients. Materials and methods An extensive literature review regarding the clinical outcome, safety and efficiency of ETV and shunting in treatment of hydrocephalus was conducted in Medline, PubMed, Cochrane and Google Scholar databases up to 27 November 2015. Patient demographics, ETV and shunting success and failure rates were extracted. Results A total of seven two-arm studies were included for quantitative analysis and 25 single-arm studies were included for systematic review. The two-arm studies recruited a total of 6995 patients: 1046 in the ETV group and 5949 in the shunt group. The pooled results showed that the 1 year success rate of ETV and shunt-placement procedure were similar (pooled RR = 0.870, 95% CI = 0.680–1.112, P = 0.266). The failure rate in the ETV treatment group was 0.9 times higher than in the shunt group; however, the results did not reach statistical significance (pooled RR = 0.893, 95% CI = 0.576–1.383, P = 0.611). Conclusions Both ETV and shunts are associated with similar 1 year success and failure rates. Therefore, there are no current indications to recommend one mode of treatment over the other. Future studies designed to assess the effectiveness of ETV and shunt procedures depending on patient’s age and etiology are warranted.

Prediction of shunt response in idiopathic normal pressure hydrocephalus by combined lumbar infusion test and preoperative imaging scoring.

Idiopathic normal pressure hydrocephalus (iNPH) is a potentially treatable disorder, but prognostic tests or biomarkers are lacking. The aim was to study the predictive power of clinical, neuroimaging and lumbar infusion test parameters (resistance to outflow Rout , cardiac-related pulse amplitude PA and the PA to intracranial pressure ICP ratio). In all, 127 patients diagnosed with iNPH who had a lumbar infusion test, a subsequent ventriculo-peritoneal shunt operation and at least 2 months of postoperative follow-up were retrospectively included. Preoperative magnetic resonance images were visually scored for NPH features using the iNPH Radscale. Preoperative and postoperative assessment was performed using cognitive testing, as well as gait and incontinence scales. At follow-up (7.4 months, range 2-20 months), an overall positive response was seen in 82% of the patients. Gait was more severely impaired at baseline in responders compared to non-responders. The iNPH Radscale score was borderline significantly higher in responders compared with non-responders, whereas no significant differences in infusion test parameters were seen between responders and non-responders. Infusion test parameters performed modestly with high positive (75%-92%) but low negative (17%-23%) predictive values. Although not significant, PA and PA/ICP seemed to perform better than Rout , and the odds ratio for shunt response seemed to increase in patients with higher PA/ICP, especially in patients with lower iNPH Radscale scores. Although only indicative, lumbar infusion test results increased the likelihood of a positive shunt outcome. Pulse amplitude measures showed promising results that should be further explored in prospective studies.

Two-point fixation enhanced the outcome of laparoscopy-assisted ventriculoperitoneal shunt in adult patients with hydrocephalus: a retrospective study.

In patients with hydrocephalus, laparoscopy significantly improved ventriculoperitoneal shunt (VPS) outcomes. However, abdominal complications still occur, which require revision surgeries. In this study, we aimed to examine whether laparoscopy-assisted VPS with two-point fixation (LAVPS-TPF) has better outcomes than those of VPS (open-VPS) and laparoscopy-assisted VPS with no fixation (LAVPS-NF). We retrospectively reviewed clinical records of 105 open-VPS, 40 LAVPS-NF, and 49 LAVPS-TPF cases from 2015 to 2020. Data including body mass index, etiology, abdominal surgery history, Glasgow coma scale (GCS), operation time, in-hospital days, shunt failure, complications, and modified Rankin scores were analyzed, as well as subgroups of patients with history of abdominal surgery, GCS scores, and revision surgeries. The LAVPS-TPF group demonstrated decreased shunt failure rates at 12 months (2.04%) compared to those of the open-VPS group (14.29%, P = 0.020) and reduced abdominal shunt-related complications (P = 0.004 vs. open-VPS and LAVPS-NF) and shunt revisions. In the LAVPS-TPF group with abdominal history (n = 51), 12-month shunt failure rates (P = 0.020 vs. open-VS), repair frequency (P = 0.020 vs. open-VS), and abdominal complications (P = 0.003 and 0.006 vs. open-VS and LAVPS-NF) were reduced. In the LAVPS-TPF group with GCS scores of 13-15 (n = 152), shunt failure rates at 12 months, abdominal complications, and revision frequency were decreased (P < 0.05 vs. other groups). Compared to the LAVPS-NF group, neurological complications were also reduced (P = 0.001). Among revision surgeries (n = 28), fixed shunts resulted in improved shunt survival rates at 12 months, reduced abdominal complications, and secondary revisions (P < 0.05). Moreover, a more optimal recovery without neurological sequelae was achieved by shunt fixation than that by LAVPS-NF (P < 0.01). LAVPS-TPF significantly improved shunt survival rates at 12 months and reduced the incidence of abdominal shunt-related complications compared to open-VPS and LAVPS-NF, especially in patients with history of abdominal surgery, higher GCS scores, and revision surgeries. However, further studies are required to confirm these benefits.

Ventriculopleural shunt outcomes for pediatric hydrocephalus: a single-institution experience.

The aim of this study is to analyze rates of ventriculopleural (VPL) shunt failure and complications among patients with pediatric hydrocephalus, and to analyze which factors may predict early (< 1year) or late (> 1year) VPL shunt failure in this sample. A retrospective chart review was conducted of all consecutive VPL shunt placements from 2000 to 2019 at our institution. Data was collected on patient characteristics, shunt history, and shunt type. Primary endpoints include rates of VPL shunt survival and rates of symptomatic pleural effusion. The Kaplan-Meier method was used to calculate shunt survival, and Fisher's exact test and t-test were used to compare differences between categorical variables and means, respectively (p < 0.05). Thirty-one patients with pediatric hydrocephalus underwent VPL shunt placement (mean age 14.2years). Of the 27 patients with long-term follow-up (mean 46months), VPL shunt revision was required in 19, seven of which were due to pleural effusion. Overall shunt survival rates at 1, 3, 5, and 7years were 76%, 62%, 55%, and 46%, respectively. Mean duration of shunt survival was 26.74months. Overall pleural effusion rate was 26%. No patient-specific factors, including shunt valve type, were significantly associated with shunt survival, risk of early revision, or risk of pleural effusion. Our results are comparable to those reported in the literature and represent one of the largest case series on the topic. VPL shunts are a viable second-line option when ventriculoperitoneal (VP) shunt placement is not possible or desirable, though there are high rates of shunt revision and pleural effusion.

Choroid plexus-targeted NKCC1 overexpression to treat post-hemorrhagic hydrocephalus

Post-hemorrhagic hydrocephalus (PHH) refers to a life-threatening accumulation of cerebrospinal fluid (CSF) that occurs following intraventricular hemorrhage (IVH). An incomplete understanding of this variably progressive condition has hampered the development of new therapies beyond serial neurosurgical interventions. Here, we show a key role for the bidirectional Na-K-Cl cotransporter, NKCC1, in the choroid plexus (ChP) to mitigate PHH. Mimicking IVH with intraventricular blood led to increased CSF [K+] and triggered cytosolic calcium activity in ChP epithelial cells, which was followed by NKCC1 activation. ChP-targeted adeno-associated viral (AAV)-NKCC1 prevented blood-induced ventriculomegaly and led to persistently increased CSF clearance capacity. These data demonstrate that intraventricular blood triggered a trans-choroidal, NKCC1-dependent CSF clearance mechanism. Inactive, phosphodeficient AAV-NKCC1-NT51 failed to mitigate ventriculomegaly. Excessive CSF [K+] fluctuations correlated with permanent shunting outcome in humans following hemorrhagic stroke, suggesting targeted gene therapy as a potential treatment to mitigate intracranial fluid accumulation following hemorrhage.

Routine versus selective near-infrared spectroscopy-guided shunting during carotid eversion endarterectomy.

The aim of this study was to compare outcomes of routine shunting to near-infrared spectroscopy (NIRS)-guided shunting in patients undergoing eversion endarterectomy (EEA) under general anaesthesia. We retrospectively evaluated data of all patients undergoing EEA of the internal carotid artery (ICA) in our department from January 2011 until January 2019. Included were patients with EEA of the ICA and the patients were divided into 2 groups: selective-shunting group and routine-shunting group. Patients (i) with patch angioplasty during the surgery, (ii) undergoing surgery for restenosis and (ii) stenosis after radiation therapy, (iii) without recorded regional cerebral oxygen saturation trends, (iv) presenting with an emergency treatment indication and (v) operated upon by residents were excluded. In all patients, EEA was performed in general anaesthesia and under NIRS monitoring. One-to-one propensity score matching was used to compare EEA outcomes after routine shunting to NIRS-guided shunting. Primary end points were defined as perioperative stroke and in-hospital mortality after EEA. Routine and NIRS-guided selective shunting were applied in 340 (34.0%) and 661 (66.0%) patients, respectively. A total of 277 pairs were generated via propensity score matching. Fifty-eight (20.1%) from the selective-shunting group were intraoperatively shunted. Concomitant procedures were more frequently performed in the routine-shunting group [170 (61.4%) vs 47 (17.0%), 180 (65%) vs 101 (36.5%), and 60 (21.7%) vs 6 (2.2%), P < 0.001]. The perioperative stroke rate in the routine-shunting group was higher as well [11 (4.0%) vs 3 (1.1%), P = 0.022]. In-hospital death was overall 0.2% (n = 1). Multivariable logistic regression in the matched patient indicated age (odds ratio 1.050, 95% confidence interval 1.002-1.104, P = 0.046) and routine shunting (odds ratio 2.788, confidence interval 1.119-7.428, P = 0.032) as risk factors for perioperative stroke during EEA of the ICA. We found that, during EEA of the ICA, under general anaesthesia, NIRS-guided selective shunting was associated with a lower incidence of perioperative stroke than routine shunting.

In Reply: Cerebrospinal Fluid Shunting for Idiopathic Intracranial Hypertension: A Systematic Review, Meta-Analysis, and Implications for a Modern Management Protocol.

To the Editor: We thank the authors1 for their excellent comments on our article2 and the editor for inviting us to respond. We agree with the authors that idiopathic intracranial hypertension (IIH) is a metabolic disease with many systemic manifestations. Besides patients often have risk of cardiovascular disease, presence of insulin resistance, increased truncal adiposity, hyperleptinemia, fertility, and pregnancy as you pointed out. In the clinical setting, these patients are initially seen and evaluated by neurologists and ophthalmologists. Patients with severe, refractory, or progressive symptoms, or those who do not tolerate medical management, are often referred to neurosurgeons for surgical intervention. Thus, in this article, we as neurosurgeons mainly focused on the outcomes of one of the common surgical interventions—cerebrospinal fluid shunting, rather than focusing on the diagnostic criteria. The included 15 studies were performed between 1988 and 2019, and 13 of them were published within past 20 years. In these studies, the diagnosis of IIH was generally based on “modified Dandy criteria,” which were introduced in 1985, and amended into “Friedman criteria” in 2002. At the end of the discussion, we proposed implications for a modern management protocol by combining the results of our meta-analysis with other management options through a comprehensive literature review. Indeed, at the discussion, papilledema was briefly discussed in both results of our meta-analysis and current management protocol section. In Figure 6, where we proposed current management strategy, visual symptoms and signs including papilledema were categorized into visual disturbances. We did not have extensive discussion on papilledema as the authors pointed out. There are a few reasons for that. One, in our meta-analysis, the focus was the outcomes of cerebrospinal fluid shunting, and in the modern management protocol, different management strategies were the focus. Two, as we described in the limitations of our study, some studies were performed by different specialties focusing on different outcomes. Studies reported by neurosurgeons focused on headaches and qualitative assessment of visual symptoms while ophthalmologists quantitively evaluated visual fields and visual acuity outcomes. Three, to cover all important aspects in the recommended management protocol and meanwhile not to exceed word count limit of the journal, lengthy discussions on a single aspect of the protocol were avoided. As the authors mentioned, there is indeed lack of randomized clinical trials for venous sinus stenting as a management option for idiopathic intracranial hypertension. However, many retrospective and prospective studies have shown favorable outcomes of venous sinus stenting for IIH.3-5 The meta-analysis by Nicholson et al5 reported excellent safety profile and significant improvements in headaches, pulsatile tinnitus, and papilledema after venous sinus stenting. There was moderate heterogeneity between included studies. In the end, we made a slight adjustment to figure 6 from original manuscript by taking the authors' feedback into account (Figure).FIGURE.: Adjusted current management strategy of IIH. BMI, body mass index; IIH, idiopathic intracranial hypertension.

Transjugular Intrahepatic Portosystemic Shunt Outcomes in the Elderly Population: A Systematic Review and Meta-Analysis.

Transjugular intrahepatic portosystemic shunt (TIPS) is a procedure typically utilized to treat refractory ascites and variceal bleeding. However, TIPS can lead to significant complications, most commonly hepatic encephalopathy (HE). Advanced age has been described as a risk factor for HE, as the elderly population tends to have decreased cognitive reserve and increased sarcopenia. We conducted a systematic review and meta-analysis of the available literature to summarize the association between advanced age and risk of adverse events after undergoing TIPS. A comprehensive search strategy to identify reports of specific outcomes (HE, 30-day and 90-day mortality, and 30-day readmission due to HE) in elderly patients after undergoing TIPS was developed in Embase (Embase.com, Elsevier). We compared outcomes and performed separate data analyses for patients aged < 70 vs. > 70 years and patients aged < 65 vs. > 65 years. Six studies with a total of 1,591 patients met our inclusion criteria and were included in the final meta-analysis. Three studies divided patients by age < 65 vs. > 65 years, with a total of 816 patients who were 54% male. The remaining three studies divided patients by age < 70 vs. > 70 years, with a total of 775 patients who were 63% male. Results demonstrated a significantly lower risk of post-TIPS HE (risk ratio (RR): 0.42, confidence interval (CI): 0.185 - 0.953, P = 0.03, I2 = 49%), 30-day mortality (RR: 0.37, CI: 0.188 - 0.74, P = 0.005, I2 = 0%), and 90-day mortality (RR: 0.35, CI: 0.24 - 0.49, P = 0.001, I2 = 0%) in patients aged > 70 vs. < 70 years, as well as a trend towards lower risk of 30-day readmission due to HE. There was no significant difference in post-TIPS HE, 30-day or 90-day mortality, or 30-day readmission due to HE between patients aged < 65 vs. > 65 years. Age > 70 years is associated with significantly higher rates of HE and 30-day and 90-day mortality rates in patients after undergoing TIPS, as well as a trend towards higher 30-day readmission due to HE.

Long-term recovery behavior of brain tissue in hydrocephalus patients after shunting

The unpredictable complexities in hydrocephalus shunt outcomes may be related to the recovery behavior of brain tissue after shunting. The simulated cerebrospinal fluid (CSF) velocity and intracranial pressure (ICP) over 15 months after shunting were validated by experimental data. The mean strain and creep of the brain had notable changes after shunting and their trends were monotonic. The highest stiffness of the hydrocephalic brain was in the first consolidation phase (between pre-shunting to 1 month after shunting). The viscous component overcame and damped the input load in the third consolidation phase (after the fifteenth month) and changes in brain volume were stopped. The long-intracranial elastance (long-IE) changed oscillatory after shunting and there was not a linear relationship between long-IE and ICP. We showed the long-term effect of the viscous component on brain recovery behavior of hydrocephalic brain. The results shed light on the brain recovery mechanism after shunting and the mechanisms for shunt failure.